Intro: Off the Grid Shed-cave
Before completing my workshed/mancave, dubbed the Shed-cave, I knew I would be needing an environment in which I will be able to operate my electric power tools, charge the cordless batteries and smartphone, work late in the night, and relax with T.V and games without installing a subpanel or siphoning power from the house via an extension. It was then I decided that my epic build (a simple 12x12 shed) would not be labeled complete until it's off the grid. So I would build the shed by day (6 months working between work). And by night, like the modern researchers of our time, armed with a cup of joe and youthful (middle age) enthusiasm, I clawed my way to the computer to bravely begin my quest...Cortana, search for free energy.
Word of advice! Free energy equipment can be very pricey so please have a budget in mind. It's always best to start small and add as the need arises.
Step 1: What I Need for Free Energy
Google informed me that for a basic free energy system setup I'm going to need: a power source; something to regulate the power; something to store the power and something to convert the stored power to usable AC. In other words, I would need solar panels or/and a wind generator; a solar and wind charge controller; batteries (deep cycle preferably) and an inverter. My intention was to harness both solar and wind energy. However, since I was only able to complete the solar, from this point forward the information given will be about harnessing solar energy.
Step 2: Power Source
Before purchasing solar panels, one should determine how much energy one will need. It's the batteries that supply voltage to the inverter. Nevertheless, if the batteries are being depleted faster than they are being charged, then there will be a problem. Solar panels should be able to keep the batteries adequately charged. Because of my intended usage for the Shed-cave and my budget, I decided to go with a 12V 100w Polycrystalline panel. This would provide me with 5A of current in direct sunlight. And as I mentioned earlier, if I need more I can always add. The panel cost me on the Bay $98.34
Ps. There are other types of panels monocrystalline (more expensive) and higher panels with higher voltages 24V.
Step 3: Location of Power Source
Most people find it easier to install the panels on their roof. But owing to the location of my Shed-cave, the roof (too many trees) was just out of the question for me. Also, the panels have to be clean from time to time (panels on roof = too much work). I needed a sunny spot that was close to the shed. A spot where I would have sun both in the summer and winter months. After watching the sun rising and falling for a few days, and the consultation of my resident solar astronomer (my wife the Gardner) I choose a location just 19 ft from the shed and about 24 ft from the charge controller and batteries.The proximity is important because it helps to determine the size wires I need to efficiently transport the juice to the batteries.
I then chose 10 AWG solar wires. Research showed that 8AWG would have been ideal (bigger wire=less heat loss over the distance). But in the imperfect world of not having all the resources at one's disposal, the 10 AWG wire would have to do. If I ever decided to add 2 more panels, in parallel, to draw more current, then I will have to increase the wire size. I found 1 pair of 50ft wire with MC4 connector for $33.85 on the bay.
Next was the mounting of the panel and the laying of the wires. The panel needed to face a southerly direction because I'm in the northern hemisphere (and I thought living in the south means I was in the southern hemisphere) and it had to be angled at certain degrees each season for maximum solar rays. You can also leave it fixed at a set angle. A quick search will yield how to calculate this. I chose to adjust the panels twice a year, summer and winter. So I built a tiltable solar mount with material from Home Depot $40 + some wood scraps I had. I also bought the electrical conduits from the big box store.
Step 4: Regulating the Power
Connecting the batteries directly to the panels is a very bad idea. Your batteries will be damaged and possibly explode from overcharging without a regulator or controller. Spend a little more, and save more the long haul.
Controllers ranged from the basic 1 or two-stage controls to the middle range PWM (pulse width modulated) to best MPPT ( maximum power point tracking). The best is always more expensive. Furthermore, I needed a controller that can also handle wind energy. So I chose a 12V 400 amp, 10k watt charge controller for wind turbine and solar panels from Missouri Wind and Solar which only set me back $69.78 on the Bay.
Step 5: Storing the Power
When I first start this project, I immediately thought that a car battery will be able to work. Afterall a battery is a battery and car batteries are reasonably priced. But I was soon schooled by the Internet University. Car batteries, even though they can work, would not be adequate for long-term storage of energy. I would have to use deep cycle batteries. Of course, anything deep would mean I have to dig deep in my pocket. These batteries are rated by the amp-hours. The more amp-hour a battery can give, the more it is going to cost. I settled on a 12V 35ah battery. In fact, I bought 2 which I connected in parallel (to increase current and maintain voltage). This would theoretically double my amps but keep the battery banks at 12V. This set me back $122.95 on the Bay.
To connect 2 batteries in parallel, you connect the positive terminals together, and the negative terminals together. Then the load and/or source is connected to the positive terminal of one battery and the negative terminal of the other. I used 1/0 AWG pure copper wires for the connecting of the batteries. This ensures minimum power loss between the battery connections.
I failed to mention earlier that your voltage rating needs to remain the same throughout your devices. That is, if you are using 12v panels, you need to use a 12v controller with a12v battery array.
Step 6: Converting the DC to AC
The current up to this point is DC. In order to operate your appliances and tools, you need the convert this DC to AC. This is where an inverter comes. Inverters come in different wattage. Also, there is the continuous watt and the peak watts. For instance, a 500-watt inverter could have a peak watt of 1000. The peak would normally double (or more) the rated watts. This peak watt is important because most motor devices need to double its wattage (called a surge) at start-up. For example, a 120v 5.8 amp device needs 696 watts to run continuously (P=IV). However, it needs 1392 watts to get going.
Then there is the Pure Sine Wave, Modified Sine Wave, and the Square Wave inverter. The PSW is more expensive and should do all that you need without no problem. It's the same wave you get from the utility company or a generator. It is reported that MSW inverter causes some batteries to overheat while being charged, along with noise in some lights, and malfunctioning of some motor devices. SW is the cheapest and the most problematic of all. I'm using a Radio Shack 350W PSW inverter that I had for a number of years now. I will have to get a higher wattage PSW inverter ( 1.5kW / 3kW ) in the future.
Step 7: The Connection
Choose the best location to mount your devices. Follow the manufacturer recommendations for connecting your panels to your charge controller and the controller to the batteries. I used 10AWG wires for all my connections from the panels to the batteries. I added a Watt Meter between the solar panel and charge controller and a power meter on the inverter. This is just to monitor what is coming in and what is going out. Not necessary for the operation.
I used a breaker box and ran a couple of switches and outlet (using a power strip would work just fine). I also connected a 20w and a 5w light.
It was also recommended to add ground (earth) to the circuit. So I added 2 (1 for the shed and 1 for the solar panel) and grounded the batteries; charge controller; inverter; solar panels and breaker (pretty much anything with metal).
Step 8: Tada
One of my testing setup.
Step 9: Tada #2
That's all folks. I hope this information was of some assistance.
Born_to_build made it!